During the festival, Montresor runs into Fortunato and pretends to be his friend while making sure that he is inebriated. Fortunato is informed by Montresor that he has a costly and rare cask of Amontillado and is asked for his judgment on it. Montresor is aware that Fortunato will be powerless to decline such an offer. He persuades Fortunato to accompany him to his palazzo, where the barrel is kept.

Fortunato becomes increasingly inebriated and confused as Montresor leads him through a maze of tunnels and into the depths of his catacombs. When they get at a dim area, Montresor pulls out an Amontillado cask. Unaware that Montresor has other ideas, Fortunato is overjoyed and enthusiastically consumes the wine. Fortunato is abruptly confined to the catacombs by Montresor, who also begins to surround him with a wall. Fortunato pleads for forgiveness after realizing what is occurring too late, but Montresor ignores him and finishes building the wall.

After finishing the wall, Montresor pauses to acknowledge his accomplishment. Having exacted revenge on Fortunato, he feels a sense of fulfillment. But he quickly understands that in order to avoid being suspected, he must hide his tracks. He meticulously wipes away all traces of the crime, returning the catacombs to their former glory.